DE102008040615A1 - A fuel injection control apparatus for compensating a deviation of an amount of fuel injected from a fuel injector - Google Patents

Abstract

A fuel injection control apparatus for an internal combustion engine is provided. A controller instructs a fuel injector to inject a learning injection amount of fuel, and determines a resulting increase in a rotational speed of the engine. The control apparatus determines the amount of fuel actually injected from the fuel injector based on the increase in the rotational speed of the engine and calculates a correction factor that compensates a difference between the learning injection amount and the actual injection amount. The controller also determines a change in a load acting on a drive member of a torque transmitting mechanism. When such a change is undesirably large, the controller stops injecting the learning injection amount. The controller may determine the increase in the speed of the machine based on the degree of change in the load. This ensures the accuracy of calculating the correction factor regardless of the change in the load.

Description

Background of the invention

1. Technical field of the invention

The The present invention generally relates to a fuel injection control apparatus for an internal combustion engine operating in a common rail fuel injection system can be applied, which is designed to increase the amount of fuel learning to be injected into the machine for a difference between an amount of fuel to be injected from a fuel injector and one actually injected from the fuel injector Correct or compensate fuel quantity.

2. State of the art

Fuel injection systems are known which are designed to learn a change in the amount of fuel injected from fuel injectors due to their aging and to correct a control signal output to the fuel injector to compensate for such a change. For example, teach JP-A-2005-036788 (corresponds with US Pat. No. 6,907,861 B2 ) and JP-A-2007-138 750 (corresponds with US 2007/0112502 A1 ) such compensation techniques. In particular, fuel injection systems for diesel internal combustion engines designed to perform pre-injection prior to main injection to reduce NOx emissions and combustion noise are required to learn the amount of fuel that is actually injected into the internal combustion engine for accuracy in injecting a small amount of fuel To ensure fuel quantity from the fuel injectors.

This in JP-A-2005-036788 ( US 6907861 B2 ) operates to output a control signal to a fuel injector to inject a fuel lean into the engine and to monitor a resulting change in engine speed to correct the amount of fuel actually injected by the fuel injector to correct the control signal to compensate for a difference between the learning amount and the actual amount.

This in JP-A-2007-138 750 ( US 2007/0112502 A1 ) is configured to output a control signal to a fuel injector to inject a fuel amount into an internal combustion engine to calculate a slip amount of rotation between a drive and a driven component of a powertrain through which an output torque of the engine is transmitted; and to determine the amount of fuel actually injected from the fuel injector based on a speed increase of the engine and the slip amount to correct the control signal to compensate a difference between the learned amount and the actual amount.

however causes a direct addition of a change in one physical load to the drive component of the powertrain or an indirect addition to the driven component an increase in speed of the internal combustion engine due to the injection of the fuel quantity occurs in these, compared to when the change a load not on the drive component or the driven component is exercised, which causes an error in the calculation the actual amount of fuel in the internal combustion engine is injected based on the speed change of the Internal combustion engine results. This leads to an error Determine the correction factor based on the difference between the learned amount and the actual amount of fuel, which is injected into the internal combustion engine.

Summary of the invention

It is therefore a principal object of the invention, the disadvantages to avoid the prior art.

It Another object of the invention is a fuel control device designed to be a correction factor for use in compensating a difference between a target fuel amount and an actual amount of fuel by a Fuel injector is injected into an internal combustion engine, in Considering a change in a physical load to learn exactly which on a drive component of a torque transmission mechanism acts.

According to one aspect of the invention, there is provided a fuel injection control apparatus for an internal combustion engine that can be applied to a common rail fuel injection system for diesel engines. The fuel injection controller has (a) a speed sensor that measures a rotational speed of an internal combustion engine (internal combustion engine), and (b) a controller that operates to control an amount of fuel to be injected from a fuel injector into the internal combustion engine. When it is required to start an injection amount learning mode, the controller operates the fuel injector to inject a learning injection amount of the fuel that is an amount of the fuel to be injected into the internal combustion engine for learning a fuel injection characteristic of the fuel offinjektors is. The controller determines a speed increase of the engine by the speed sensor occurring due to the injection of the learning injection amount of the fuel, and also determines an actual injection amount of the fuel, which is an amount of the fuel that is supposed to have been injected from the fuel injector on the basis of the speed increase of the internal combustion engine. The controller calculates a correction factor based on a difference between the learned injection amount and the actual injection amount to compensate for the difference. The controller also determines a change of a load acting on a drive member of a torque transmitting mechanism by which an output torque of the engine is transmitted from the drive member to a driven member. When an absolute value of the change of the load is larger than a predetermined value, the controller stops the injection quantity learning mode.

Especially arises when the degree of change of a load, acting on the drive member is large, a reduction an accuracy of learning the injected from the fuel injector Fuel quantity. In such a case, the control device prevents that the fuel injector injects the fuel quantity, whereby the learning accuracy is ensured.

In a preferred embodiment of the invention the control device, the speed increase of the internal combustion engine based on the speed of the internal combustion engine passing through the speed sensor is measured, and the change of Load acting on the drive component.

The Control device can change the load, the acting on the drive component, based on a speed change the internal combustion engine between a time before and after the injection determine the learning injection amount of the fuel.

If a load generating object that is directly connected to the drive component is actuated, determines the controller, that the change of the load is exerted on the drive component, and also determines if the absolute value of the change the load is greater than the specified value or Not.

If an output signal from a brake sensor is an actuation a brake pedal for the internal combustion engine indicates can the controller determine that the change the load is exerted on the drive component, and also determine whether the absolute value of the change of load is greater as the default value or not.

If a gear of a transmission that in the torque transmitting mechanism is installed, the controller can determine that the change in the load is exerted on the drive component will, and also determine if the absolute value of the change the load is greater than the specified value or Not.

The Control means may alternatively the absolute value of the change the load acting on the drive component based on a difference the speed between a time before and after the injection of Learn injection amount of the fuel through the fuel injector to calculate.

The Changing the load acting on the drive component, is either a positive change in the load that is oriented is directed or acts to the speed of the internal combustion engine to reduce, or a negative change in the load that oriented to increase the speed of the internal combustion engine. The controller determines at least the positive change the load, which is very likely to be on the drive component occurs during the injection quantity learning mode.

In a case where an automatic transmission is installed in the torque-transmitting mechanism and a lock-up clutch makes a direct mechanical connection between the drive member and the driven member, or in which a manual transmission is installed in the torque-transmitting mechanism and the drive member and the driven member are connected by means of a clutch are without rotation occurs between them, the driven member is rotated together with the drive member, whereby a large amount of torsion or a change of a physical load occurs, which is applied to the drive and the driven member. This results in a change in the rotational speed of the internal combustion engine, even if the amount of fuel injected from the fuel injector is constant. Consequently, the controller may determine whether or not the drive member and the driven member are slipping on rotation. When it is determined that the drive member and the driven member are slipping on rotation, that is, if the change of the load is not directly transmitted from the driven member to the drive member, the controller starts the injection quantity learning mode, whereby the accuracy for determining the correction factor the basis of increasing the speed of burning motor is ensured.

According to one Another aspect of the invention is a fuel injection control device provided for an internal combustion engine, the (a) with a A speed sensor that measures a speed of an internal combustion engine; and (b) has a controller that operates to extract one the fuel injector in the internal combustion engine to be injected fuel amount to control. If necessary, an injection learning mode To begin, the controller has the fuel injector to inject a learning injection amount of fuel, the one Amount of fuel that is from the fuel injector to the Internal combustion engine for learning a fuel injection characteristic inject the fuel injector. The control device determines a change in a load on a drive component a torque transmitting mechanism acts through the an output torque of the internal combustion engine from the drive member is transmitted to a driven component. The control device also determines an increase in a rotational speed of the internal combustion engine, that due to the injection of the learning injection amount of the fuel occurred by the speed sensor based on the Speed of the internal combustion engine, measured by the speed sensor is, and the change in the load on the drive component acts. The controller also determines an actual one Injection amount of fuel, which is an amount of fuel from which is assumed to be actually from the fuel injector was injected on the basis of the increase in Speed of the internal combustion engine. The controller calculates a Correction factor based on a difference between the learning injection amount and the actual injection quantity to the difference for instructing the fuel injector to inject a target amount of the fuel.

Especially the controller determines the actual injection amount considering the increase in the speed of the machine, which means the accuracy of determining the correction factor independently from the change of the load acting on the drive component works, is ensured.

The Modifications described above can also be applied to be applied to the second aspect of the invention.

Brief description of the drawings

The The present invention can best be understood from the following detailed Description and the accompanying drawings of the preferred embodiments the invention are understood, but not the invention limited to the specific embodiments but for the purpose of explanation and explanation be used.

1 Fig. 10 is a block diagram illustrating a fuel injection system according to the invention;

2 (a) FIG. 15 is a graph showing changes Δω in a number of revolutions of an engine shown for every four cylinders of the engine when the driver of the vehicle has suddenly operated the brake pedal in an injection amount learning mode; FIG.

2 B) FIG. 15 is a graph showing variations Δω in a rotational speed of an internal combustion engine that occur when the accelerator pedal of the vehicle is released to decelerate the engine without injecting the fuel through fuel injectors; FIG.

3 FIG. 15 is a graph showing changes Δω in a rotational speed of an internal combustion engine occurring during deceleration of the engine before and after an injection quantity learning mode; FIG. and

4 Fig. 10 is a flowchart of a program for learning the amount of fuel actually injected from a fuel injector and calculating a correction factor for compensating a deviation of an injection characteristic of the fuel injector.

Description of the preferred embodiments

Referring to the drawings, wherein like reference numerals refer to like parts in different views, and more particularly to FIG 1 is a storage fuel injection system 10 according to the invention, which is embodied for example as a common rail fuel injection system for vehicle diesel engines.

The fuel injection system 10 has a high pressure pump 12 , a common rail 14 , Fuel injectors 24 and an electronic control unit (ECU) 50 and works to inject a fuel into a diesel engine 20 to control that via a torque converter 30 and an automatic transmission 40 is connected to driven wheels of a motor vehicle.

The high pressure pump 12 is a common known type having pistons that move in accordance with a rotation of a cam of a camshaft 22 the diesel engine 20 reciprocate to pressurize the fuel, which is sucked into pressure chambers one after the other. The ECU 50 works to the amount of current that is connected to a suction control valve (not shown), which is in the high pressure pump 12 is installed, to control, in the pressure chamber of the high-pressure pump 12 to regulate the amount of fuel sucked during a suction stroke of each piston.

The common rail 14 serves as a reservoir in which the fuel flowing from the high pressure pump 12 is promoted, stored and maintained at a high pressure based on an operating condition of the diesel engine 20 is controlled. The pressure of the fuel in the common rail 14 (hereinafter referred to as a common rail pressure) is determined by the flow rate of the fuel flowing from the high pressure pump 12 is discharged, and a pressure reducing valve (not shown) regulated in the high-pressure pump 12 is installed.

The diesel engine 20 which is described below as an example is a four-cylinder internal combustion engine. The fuel injectors 24 are each in cylinders of the diesel engine 20 installed and working to inject the fuel into the respective cylinders. The ECU 50 works to every fuel injector 24 several times to open multiple injections of fuel into the machine 20 in each engine operating cycle (that is, in a four-stroke operation) including a suction or suction, compression, working and exhaust strokes. In particular, the ECU works 50 to execute the pilot injection, the main injection and the post injection in each engine operating cycle. Every fuel injector 24 is implemented by a conventional solenoid-operated valve configured to regulate fuel pressure within a control chamber acting on a nozzle needle in a valve closing direction to flow out of the fuel injector 24 To control the amount of fuel to be injected.

The torque converter 30 and the automatic transmission 40 are installed in a powertrain (also referred to as a gear train), which has an output torque of the diesel engine 20 transfers that from the crankshaft 22 by a drive shaft 42 to driven wheels (not shown) drives. The torque converter 30 has a pump wheel 32 and a turbine wheel 34 which are arranged facing each other. The impeller 32 is with the crankshaft 22 the diesel engine 20 connected. The turbine wheel 34 is with the drive shaft 42 of the automatic transmission 40 connected.

In an operation of the torque converter 30 is the turbine wheel 34 a mass inertial force of a flow of an oil, due to the rotation of the impeller 32 occurs. A stator 36 is between the impeller 32 and the turbine runner 34 arranged and works to the flow of oil from the turbine wheel 34 to the impeller 32 to change and return, whereby the torque is increased.

The torque converter 30 works to the output torque of the diesel engine 20 to the automatic transmission 40 during a rotation, a slip between the drive shaft 42 and the crankshaft 22 the diesel engine 20 is allowed.

A lockup clutch 38 is through the ECU 50 hydraulically controlled to provide a direct connection between the crankshaft 22 and the drive shaft 42 manufacture. The engagement of the lock-up clutch 38 is controlled by a hydraulic pressure provided by a hydraulic control system for the automatic transmission 40 is produced. If the lockup clutch 38 the crankshaft 22 and the drive shaft 42 directly connects, is the slip (slip state) between the crankshaft 22 and the drive shaft 42 eliminated.

The automatic transmission 40 is a common multi-stage transmission equipped with a planetary gear set or a stepless belt or trochoid gear. The stage of the automatic transmission 40 is controlled by the ECU by controlling the hydraulic control system equipped with solenoid valves 50 changed.

The ECU 50 serves as a fuel injection control device and is provided by a conventional microcomputer consisting essentially of a CPU, a ROM, a RAM, and rewritable non-volatile memories such as a flash memory. The ECU 50 monitors output signals of a crank angle sensor 60 , a turbine speed sensor 62 , a vehicle speed sensor 64 , an accelerator position sensor 66 , an oil temperature sensor 68 and a brake sensor 70 to an operating condition of the diesel engine 20 capture. The accelerator position sensor 66 operates to measure the position of the accelerator pedal of the vehicle (that is, the degree of opening of the throttle valve). The ECU 50 also monitors operating conditions of electrical loads such as an air conditioner 80 and the generator 82 ,

The ECU 50 also works to the operating condition of the diesel engine 20 and controls the energization of the high pressure fuel pump 12 , the fuel injectors 24 , the lockup clutch 38 and the hydraulic control system of the automatic transmission 40 to the diesel engine 20 to keep in a desired state.

The ECU 50 also works to the injection timing and by the fuel injectors 24 amount of fuel to be injected (hereinafter referred to as an injection amount) based on the operating state of the diesel engine 20 to be controlled by the signal outputs of the above sensors. In particular, the ECU gives 50 an injection control pulse signal to each fuel injector 24 out to a controlled amount of fuel in the diesel engine 20 to inject at a controlled timing. The increase in the width of the injection control pulse results in a prolonged period of time in which the control chamber of each fuel injector 24 is opened to a low pressure side to increase the injection quantity. The ECU 50 stores in the ROM or the flash memory a map which lists relationships between the width of the injection control pulse and the injection amount for each common rail pressure (that is, the one from the fuel injectors) 24 to be sprayed fuel pressure).

• 1) Die ECU 50 prüft das Ausgangssignal des Kurbelwinkelsensors 60, um die Drehzahl ω der Kurbelwelle 22 (das heißt, der Dieselmaschine 20) für jeden Zylinder der Dieselmaschine 20 zu bestimmen. Die Drehzahl ω der Kurbelwelle 22 wird unmittelbar vor der Einspritzzeitabstimmung jedes Kraftstoffinjektors 24 gemessen. Die ECU 50 bestimmt eine Drehzahlveränderung Δω, die eine Differenz zwischen der Drehzahl ω der Kurbelwelle 22, die zuletzt für jeden der vier Zylinder der Dieselmaschine 20 bestimmt wurde, und der, die vor 720° CA bestimmt wurde.
• 2) Die ECU 50 gibt das Einspritzsteuerungssignal zu jedem Kraftstoffinjektor 24 aus, um die Einspritzzeitabstimmung und die Einspritzmenge zu bestimmen. Die ECU 50 beginnt ferner einen Einspritzmengenlernmodus, um den Einspritzsteuerungsimpuls, der eine Lerneinspritzmenge angibt, zu jedem der Kraftstoffinjektoren 24 auszugeben. Insbesondere weist die ECU 50 jeden Kraftstoffinjektor 24 an, um eine ausgewählte Menge (das heißt die Lerneinspritzmenge) des Kraftstoffs zum Lernen einer Kraftstoffeinspritzcharakteristik einzuspritzen.
• 3) Die ECU 50 analysiert die Drehzahlveränderung Δω, die in dem Einspritzmengenlernmodus geprüft wird, und eine Veränderung einer Last, die auf die Kurbelwelle 22 wirkt und die nachstehend beschrieben ist, um eine Erhöhung einer Drehzahl der Kurbelwelle 22 zu bestimmen, die aufgrund des Einspritzens des Kraftstoffs in dem Einspritzmengenlernmodus auftritt (der nachstehend als eine Lerneinspritzung bezeichnet ist).

The ECU 50 operates to perform control actions described below according to control programs stored in the ROM or the flash memory.

• 1) The ECU 50 checks the output signal of the crank angle sensor 60 to the rotational speed ω of the crankshaft 22 (that is, the diesel engine 20 ) for each cylinder of the diesel engine 20 to determine. The speed ω of the crankshaft 22 becomes immediately before the injection timing of each fuel injector 24 measured. The ECU 50 determines a speed change Δω, which is a difference between the rotational speed ω of the crankshaft 22 Last, for each of the four cylinders of the diesel engine 20 was determined and that determined before 720 ° CA.
• 2) The ECU 50 gives the injection control signal to each fuel injector 24 to determine injection timing and injection quantity. The ECU 50 Further, an injection quantity learning mode to start the injection control pulse indicative of a learning injection amount to each of the fuel injectors 24 issue. In particular, the ECU 50 every fuel injector 24 to inject a selected amount (that is, the learning injection amount) of the fuel for learning a fuel injection characteristic.
• 3) The ECU 50 analyzes the speed change Δω, which is checked in the injection amount learning mode, and a change of a load applied to the crankshaft 22 acts, and which is described below, to increase a rotational speed of the crankshaft 22 to be determined due to the injection of the fuel in the injection quantity learning mode (hereinafter referred to as a learning injection).

2 (a) indicates the speed changes Δω, the changes in the speed of the diesel engine 20 (ie the crankshaft 22 ) tested for the respective four cylinders when the driver of the vehicle has strongly operated the brake pedal in the injection quantity learning mode. 2 B) indicates the speed changes Δω that were tested when the accelerator pedal is released to the vehicle without injecting the fuel through the fuel injectors 24 to delay.

In the example of 2 B) For example, a change in the rotational speed variation Δω indicated by "Δ" when the learning injection is not performed is substantially in a broken line 200. which passes through the rotational speed variations Δω just checked before and after the learning injection is performed. The increase in the speed of the diesel engine 20 can therefore directly by calculating a difference between a solid line 210 representing the speed changes Δω resulting from the output signal of the crank angle sensor 60 be measured, and the dashed line 200. be found out.

In the example of 2 (a) in which there is a positive change in the load that occurs due to heavy braking on the crankshaft 22 acts, the speed changes .DELTA..omega., when the learning injection is not performed, moderately change along a dot-dash line 220 , A change in the speed changes Δω, the dashed line 200. is displayed, which is just passing through the rotational speed changes Δω, which are checked before and after the executions of the learning injection, is smaller than that indicated by the dot-dash line 220 is displayed. This causes the increase in the speed of the diesel engine 20 , which occurs due to the learning injection, is erroneously determined and is larger than the actual one, if as in 2 B) as a difference between the solid line 210 representing the speed changes Δω resulting from the output signal of the crank angle sensor 60 be measured, and the dashed line 200. is calculated.

The above error can be made by correcting or reducing the increase of the speed of the diesel engine 20 based on the size of a hatched area 230 be eliminated by the dash-dotted line 220 and the dashed line 200. is enclosed. The larger the size of the hatched area 230 which is a function of a difference in rotational speed variations Δω between the dot-dash line 220 and the dashed line 200. is, the greater the amount to increase the speed of the diesel engine 20 should be reduced.

• 4) Die ECU 50 ist gestaltet, um den Einspritzmengenlernmodus zu unterbrechen, das heißt ein Lernen oder Korrigieren der Kraftstoffeinspritzcharakteristik jedes Kraftstoffinjektors 24 zu stoppen, wenn der Grad einer Veränderung der Last auf die Kurbelwelle 20 wirkt, das heißt die Differenz der Drehzahlveränderung Δω zwischen der strichpunktierten Linie 220 und der gestrichelten Linie 200.
• 5) Die ECU 50 berechnet die Kraftstoffmenge, von der angenommen wird, dass sie tatsächlich durch die Kraftstoffinjektoren 24 eingespritzt wurde (nachstehend als eine tatsächliche Einspritzmenge bezeichnet), auf der Grundlage der Erhöhung der Drehzahl der Kurbelwelle 22, die in der vorstehenden Art und Weise bestimmt wird, in Anbetracht der Veränderung der Last auf die Kurbelwelle 22. Die ECU 50 korrigiert ferner die tatsächliche Einspritzmenge als eine Funktion eines Schlupfprozentsatzes SR, der eine Funktion einer Differenz der Drehzahl zwischen der Kurbelwelle 22 und der Antriebswelle 42 ist. Der Schlupfprozentsatz SR ist durch die nachstehende Gleichung (1) dargestellt. SR = (|NE-NO|/NE) × 100 (1)wobei NE die Drehzahl der Kurbelwelle 22 ist und NO die Drehzahl der Antriebswelle 42 ist.
• 6) Die ECU 50 berechnet eine Differenz zwischen der Lerneinspritzmenge, die, wie vorstehend beschrieben ist, eine Kraftstoffsollmenge ist, die durch jeden Kraftstoffinjektor 24 in den Einspritzmengenlernmodus einzuspritzen ist, und der tatsächlichen Einspritzmenge, um einen Korrekturfaktor zur Verwendung beim Korrigieren der Kraftstoffeinspritzcharakteristik jedes Kraftstoffinjektors 24 zu bestimmen. Die Kraftstoffeinspritzcharakteristik zeigt das Verhältnis zwischen der Breite des Einspritzsteuerungsimpulses, der zu einem entsprechenden Kraftstoffinjektor 24 auszugeben ist, und der Einspritzmenge, von der erwartet wird, dass sie aus dem entsprechenden Kraftstoffinjektor 24 gespritzt wird.
• 7) Die ECU 50 bestimmt, ob die Veränderung der Last auftritt und auf die Kurbelwelle 22 ausgeübt wird oder nicht auftritt und nicht ausgeübt wird. Die Veränderung der Last, die auf die Kurbelwelle 22 wirkt, wird in zwei Arten unterteilt: eine ist eine positive Veränderung der Last, die orientiert ist, um die Drehzahl der Kurbelwelle 22 zu verringern, und die zweite ist eine negative Veränderung der Last, die orientiert ist, um die Drehzahl der Kurbelwelle 22 zu erhöhen. Insbesondere arbeitet die ECU 50, um zu bewirken, dass die Veränderung der Last auf die Kurbelwelle 22 in den nachstehenden Fällen aufgebracht wird:
• 7a) wenn eine Differenz zwischen der Veränderungsrate 212, die in 3 gezeigt ist, der Drehzahlveränderung Δω vor der Ausführung der Lerneinspritzung und der Veränderungsrate 214 der Drehzahlveränderung Δω nach der Ausführung der Lerneinspritzung größer als ein vorgegebener Wert ist oder eine Differenz 216 zwischen den Drehzahlveränderungen Δω vor und nach der Ausführung der Lerneinspritzung größer als ein vorgegebener Wert ist;
• 7b) wenn das Ausgangssignal des Bremssensors 70 die Tatsache anzeigt, dass das Bremspedal betätigt oder freigegeben wurde;
• 7c) wenn die elektrische Last wie zum Beispiel der Klimaanlage 80 und/oder des Generators 82, die/der durch die Kurbelwelle 22 über eine mechanische Verbindung anzutreiben sind/ist, von dem ausgeschalteten zu dem eingeschalteten Zustand oder dem eingeschalteten zu dem ausgeschalteten Zustand umgeschaltet wurde; und
• 7d) wenn die Stufe des Automatikgetriebes 40 verändert wurde, wenn zum Beispiel das Automatikgetriebe 40 von der dritten Gangstufe zu der zweiten Gangstufe verändert wurde, so dass die positive Veränderung der Last auf die Kurbelwelle 22 wirkt, oder von der zweiten Gangstufe auf die dritte Gangstufe verändert wurde, so dass die negative Veränderung der Last auf die Kurbelwelle 22 wirkt.
• 8) Die ECU 50 arbeitet, um zu bestimmen, ob die Überbrückungskupplung 38 die Verbindung zwischen der Kurbelwelle 22 und der Antriebswelle 42 herstellt oder freigibt.
• 9) Die ECU 50 arbeitet, um zu bestimmen, dass eine Lernanforderung vorherrscht, wenn das Gaspedal freigegeben wird, um das Fahrzeug ohne Einspritzen des Kraftstoffs in die Dieselmaschine 20 zu verzögern und die Überbrückungskupplung 38 nicht in Eingriff ist, um zuzulassen, dass die Kurbelwelle 22 und die Antriebswelle 42 bei einer Drehung rutschen.

Alternatively, the increase in the speed of the diesel engine 20 from the dot-dash line 220 to the solid line 210 also be calculated on the basis of the speed changes Δω, by the dashed line 220 are shown. The dash-dotted line 220 can mathematically by means of a rate of change 212 , as in 3 shown is the speed of the diesel engine 20 before the execution of the learning injection and a rate of change 214 the speed of the diesel engine 20 be derived after the execution of the learning injection.

• 4) The ECU 50 is configured to interrupt the injection quantity learning mode, that is, learning or correcting the fuel injection characteristic of each fuel injector 24 to stop when the degree of change in the load on the crankshaft 20 acts, that is, the difference of the speed change Δω between the dot-dash line 220 and the dashed line 200. ,
• 5) The ECU 50 calculates the amount of fuel that is supposed to actually flow through the fuel injectors 24 was injected (hereinafter referred to as an actual injection amount) based on the increase in the rotational speed of the crankshaft 22 , which is determined in the above manner, in consideration of the change of the load on the crankshaft 22 , The ECU 50 further corrects the actual injection amount as a function of a slip percentage SR that is a function of a difference in rotational speed between the crankshaft 22 and the drive shaft 42 is. The slip percentage SR is represented by the following equation (1). SR = (| NE-NO | / NE) × 100 (1) where NE is the speed of the crankshaft 22 and NO is the speed of the drive shaft 42 is.
• 6) The ECU 50 calculates a difference between the learning injection amount which, as described above, is a target fuel amount passing through each fuel injector 24 is to be injected into the injection quantity learning mode, and the actual injection amount is a correction factor for use in correcting the fuel injection characteristic of each fuel injector 24 to determine. The fuel injection characteristic shows the ratio between the width of the injection control pulse applied to a corresponding fuel injector 24 and the injection amount that is expected to be emitted from the corresponding fuel injector 24 is injected.
• 7) The ECU 50 Determines whether the change in load occurs and on the crankshaft 22 is exercised or does not occur and is not exercised. The change of load on the crankshaft 22 is divided into two types: one is a positive change in the load, which is oriented to the speed of the crankshaft 22 reduce, and the second is a negative change in the load, which is oriented to the speed of the crankshaft 22 to increase. In particular, the ECU works 50 to cause the change of load on the crankshaft 22 applied in the following cases:
• 7a) if a difference between the rate of change 212 , in the 3 is shown, the speed change Δω before the execution of the learning injection and the rate of change 214 the speed change Δω after the execution of the learning injection is greater than a predetermined value or a difference 216 between the speed changes Δω before and after the execution of the learning injection is greater than a predetermined value;
• 7b) when the output signal of the brake sensor 70 indicates the fact that the brake pedal has been actuated or released;
• 7c) when the electrical load such as the air conditioning 80 and / or the generator 82 passing through the crankshaft 22 to be driven via a mechanical connection, has been switched from the off to the on state or the on state to the off state; and
• 7d) if the stage of the automatic transmission 40 was changed, for example, if the automatic transmission 40 from the third gear to the second gear has been changed, so that the positive change in the load on the crankshaft 22 acts, or was changed from the second gear to the third gear, so that the negative change in the load on the crankshaft 22 acts.
• 8) The ECU 50 works to determine if the lock-up clutch 38 the connection between the crankshaft 22 and the drive shaft 42 produces or releases.
• 9) The ECU 50 operates to determine that a learning request prevails when the accelerator pedal is released to the vehicle without injecting the fuel into the diesel engine 20 to delay and the lock-up clutch 38 not engaged, to allow the crankshaft 22 and the drive shaft 42 slip with one turn.

The operation of the ECU 50 in the injection amount learning mode will be described below in detail with reference to a flowchart in FIG 4 described. The program that is in 4 is in the ROM or the flash memory in the ECU 50 is stored and executed each time an injection timing for controlling fuel injection into each of the four cylinders of the diesel engine machine 20 is reached.

After starting the program, the routine goes to a step 300 in which it is determined whether the learning request for learning the fuel injection characteristic of each fuel injector 24 prevails or does not prevail. For example, when the accelerator pedal is released, it determines the diesel engine 20 without injecting the fuel through the fuel injectors 24 to decelerate, so that the speed of the crankshaft 22 decreases at a constant rate and the lock-up clutch 38 not engaged, to allow the crankshaft 22 and the drive shaft 42 slip with one turn, the ECU 50 in that the learning requirement prevails. If NO is obtained as the answer, that is, the learning request does not prevail, then the routine is ended.

If YES in the step 300 is obtained, then the routine goes to a step 302 in which the ECU 50 the injection learning mode starts and the injection control pulse to a corresponding injector of the fuel injectors 24 to provide a single injection of fuel of an amount selected to learn the fuel injection characteristic. The amount of fuel coming out of the fuel injector 24 is injected in the injection quantity learning mode is selected to be identical to that of the conventional pilot injection. The ECU 50 Alternatively, it may be configured to provide a sequence of injections of fuel in a corresponding one of the cylinders of the diesel engine 20 perform. In this case, the ECU shares 50 the amount of fuel by increasing the speed of the crankshaft 22 in a subsequent step, by the number of sequences of injections and defines them as the amount of fuel used in one of the injection events.

The routine moves to a step 304 in which it is determined whether a change in the load on the crankshaft 22 during the injection quantity learning mode (for example, checking the change in the rotational speed of the crankshaft 22 ) or not. In particular, the ECU determines 50 that change the load on the crankshaft 22 acted when the brake pedal was pressed. The ECU 50 may alternatively be designed to such a determination (as described above in the section 7) based on the change of the stage of the automatic transmission 40 , the operating condition of the air conditioner 80 or the generator 82 and / or a change in the speed change .DELTA..omega.

If NO in the step 304 This means that the brake pedal is not actuated, leaving no change in the load on the crankshaft 22 is applied, it is determined that the speed variation Δω when the learning injection is not performed along the broken line 200. changed, as in 2 B) is shown. The routine then proceeds to a step 306 progressing, in which the increase in the speed of the crankshaft 22 from a difference between the speed change Δω, the solid line 210 is shown and which occurs when the learning injection is carried out, and the speed change Δω is calculated by the dashed line 200. is shown and that occurs when the learning injection is not executed. The routine then proceeds to a step 312 Ahead.

Alternatively, if NO in the step 304 This means that the brake pedal is pressed to change the load on the crankshaft 22 Alternatively, the routine proceeds to a step 308 in which it is determined whether or not an absolute value of the change of the load is larger than a predetermined value. As described above, the value of the variation of the load becomes a difference of the rotational speed change Δω between the dot-dash line 220 and the dashed line 200. in 2 (a) calculated. The value of the load change may alternatively be a difference between the rate of change 212 , as in 3 is shown, the speed change Δω before the execution of the learning injection and the rate of change 214 the speed change Δω after the execution of the learning injection or a difference 216 between the speed change Δω before and after the execution of the learning injection are derived.

If YES in the step 308 This means that the change in load is too great to be in the diesel engine 20 to accurately correct the amount of fuel to be injected, then the routine will be without correcting the fuel injection characteristic of a corresponding injector of the fuel injectors 24 completed.

Alternatively, if NO in the step 308 is obtained, then the routine goes to a step 310 in which a difference of the speed change Δω between the dot-dash line 220 and the dashed line 200. from a difference of the speed change Δω between the solid line 210 and the dashed line 200. is subtracted to increase the speed change Δω, that is, the increase of the rotational speed of the crankshaft 22 to be determined due to the learning injection. The increase in the rotational speed may alternatively, as described above, by defining the Drehzahlverän tion .DELTA..omega., through the dash-dotted line 220 is displayed as a reference speed change and by calculating a derivative of the speed change Δω by the solid line 210 is indicated, by the determined by the dash-dotted line 220 is displayed.

The routine moves to a step 312 in which the actual injection quantity, that is the amount of fuel, is assumed to be actually received by a corresponding injector of the fuel injectors 24 was injected, calculated on the basis of the increase in speed, either in the step 306 or 310 was derived. The ECU 50 Further, a difference between the actual injection amount and the learning injection amount, that is, as described above, calculates a target fuel injection amount by the corresponding injector of the fuel injectors 24 in the injection amount learning mode is to be the correction factor for use in correcting the fuel injection characteristic of the corresponding injector of the fuel injectors 24 to determine the ratio between the width of the fuel injector to the corresponding injector 24 shows the injection control pulse to be output and the injection quantity to be expected from this.

The ECU 50 is, as described above, designed to increase the rotational speed of the crankshaft 22 based on the change in the load acting on the crankshaft 22 acts, which is a drive member of the powertrain (that is, a torque transmitting mechanism), to accurately correct when it is determined that the change of the load on the crankshaft 22 during the injection amount learning mode, whereby the accuracy in determining the actual injection amount by the corrected increase in the rotational speed is ensured, by the correction factor based on the difference between the actual injection amount and the learning injection amount for correcting the fuel injection from one of the fuel injectors 24 derive fuel quantity to be injected. This enables a small amount of fuel to be injected, for example, in the pilot injection before the main injection, to be accurately determined in the common rail fuel injection systems.

The increase in the speed of the crankshaft 22 As described above, as described above, it is determined by the difference of the rotational speed variation Δω between the times when the learning fuel injection is executed and when it is not performed, and may be represented by a difference between the rotational speed ω of the crankshaft 22 directly through the crank angle sensor 60 is measured when the learning injection is performed, and the rotational speed ω of the crankshaft 22 be determined at the same crank angle when the learning injection is not executed. The speed ω of the crankshaft 22 with a crank angle leading to a selected cylinder of the cylinder of the diesel engine 20 corresponds, when the learning injection is not executed, mathematically from a rate of change of the rotational speed of the crankshaft 22 be calculated before the execution of the learning injection.

In the program of 4 stops when the degree of change in the load acting on the crankshaft 22 is applied, which has occurred due to the operation of the brake pedal is greater than the predetermined value, the ECU 50 learning the fuel injection characteristic, that is, determining the correction factor for the fuel injectors 24 but it can alternatively be designed to the operating state of the brake pedal, the automatic transmission 40 , the air conditioning 80 or the generator 82 to monitor and stop the determination of the correction factor when the monitored state indicates that the change in the load on the crankshaft 22 is exercised. For example, the value with which the absolute value of the change in the load on the crankshaft 22 in the step 308 is set to a very small value or set to zero, so that if YES in the step 304 the routine gets through the step 308 is terminated without the correction factor being determined.

The ECU 50 may alternatively be designed to increase the speed change Δω in the step 310 to calculate without the degree of change of the load with the predetermined value in the step 308 is compared whenever it is in the step 304 It is determined that the change of load on the crankshaft 22 is exercised.

Instead of the automatic transmission 40 a manual transmission can be used in which the drive shaft 42 through a coupling with the crankshaft 22 connected is. In this case, the ECU 50 determine that the learning requirement prevails when the clutch is not engaged.

The ECU 50 in the above embodiment, to learn the amount of fuel that is in the pilot injection mode in the fuel injection system 10 inject the fuel that is in the common rail 14 is stored in each of the cylinders of the diesel engine 20 through one of the fuel injectors 24 but it may alternatively be configured to learn the amount of fuel injected in the main injection mode or the post-injection mode after the main injection mode.

The invention may be applied to a fuel injection system which injects the fuel into a gasoline engine through fuel injectors without the common rail 14 is used.

While the present invention with respect to the preferred embodiments should be described in order to facilitate their understanding It should be noted that the invention in different ways without departing from the scope of the invention can be. Therefore, it goes without saying that the Invention all possible embodiments and modifications in the embodiments shown may include, without departing from the scope of the invention according to the appended claims can be executed.

One Fuel injection control device for an internal combustion engine is provided. A control device has a fuel injector to inject a learning injection amount of a fuel, and determines a resulting increase in a speed the machine. The controller determines the amount of Fuel actually from the fuel injector is injected based on the increase in the speed the machine and calculates a correction factor, which is a difference between the learning injection amount and the actual injection amount compensated. The controller also determines a change in a Load acting on a drive component of a torque transmission mechanism acts. If such a change is undesirable is large, the controller stops injecting the learning injection amount. The controller may increase the speed of the machine based on the degree of change determine the load. This represents the accuracy of the calculation of the Correction factor independent of the change the load for sure.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - JP 2005-036788 A [0002, 0003]
• US 6907861 B2 [0002, 0003]
• - JP 2007-138750 A [0002, 0004]
• US 2007/0112502 A1 [0002, 0004]

Claims (17)

Fuel injection control device for an internal combustion engine ( 20 ) with: a speed sensor ( 60 ), the speed of an internal combustion engine ( 20 ) measures; and a control device ( 50 ), which works to get a from a fuel injector ( 24 ) in the internal combustion engine ( 20 ) to control the amount of fuel to be injected, wherein, when it is necessary to start an injection amount learning mode, the controller ( 50 ) the fuel injector ( 24 ) to inject a learning injection amount of the fuel, which is an amount of in the internal combustion engine ( 20 ) fuel to be injected for learning a fuel injection characteristic of the fuel injector ( 24 ), the control device ( 50 ) an increase in the speed of the internal combustion engine ( 20 ) occurred due to the injection of the learning injection amount of the fuel, by the rotational speed sensor ( 60 ) and also an actual injection quantity of the fuel, which is an amount of fuel that is assumed to be actually received by the fuel injector (FIG. 24 ) was injected on the basis of the increase in the number of revolutions of the internal combustion engine ( 20 ), the control device ( 50 ) calculates a correction factor based on a difference between the learning injection amount and the actual injection amount for compensating the difference, the controller (16) 50 ) also determines a change in a load that is due to a drive component ( 22 ) of a torque transmission mechanism, by which an output torque of the internal combustion engine ( 20 ) of the drive component ( 22 ) is transmitted to a driven component, wherein, if an absolute value of the change of the load is greater than a predetermined value, the control device ( 50 ) interrupts the injection learning mode. A fuel injection control apparatus according to claim 1, wherein said control means ( 50 ) the increase in the speed of the internal combustion engine ( 20 ) based on the speed of the internal combustion engine ( 20 ) by the speed sensor ( 60 ) and the change in load applied to the drive component ( 22 ) acts. A fuel injection control apparatus according to claim 1, wherein said control means ( 50 ) the change in the load on the drive component ( 22 ) acts on the basis of a change in the rotational speed of the internal combustion engine ( 20 ) between a time before and after injecting the learning injection amount of the fuel. A fuel injection control apparatus according to claim 1, wherein, when a load generating object is directly connected to said drive member (10). 22 ) is actuated, the control device ( 50 ) determines that the change in the load on the drive component ( 22 ), and also determines whether or not the absolute value of the variation of the load is greater than the predetermined value. A fuel injection control apparatus according to claim 1, wherein when an output signal from a brake sensor ( 70 ) an actuation of a brake pedal for the internal combustion engine ( 20 ), the control device ( 50 ) determines that the change in the load on the drive component ( 22 ), and also determines whether or not the absolute value of the variation of the load is greater than the predetermined value. A fuel injection control apparatus according to claim 1, wherein when a gear of a transmission ( 40 ), which is installed in the torque-transmitting mechanism is changed, the control device ( 50 ) determines that the change in the load on the drive component ( 22 ), and also determines whether or not the absolute value of the variation of the load is greater than the predetermined value. A fuel injection control apparatus according to claim 1, wherein said control means ( 50 ) the absolute value of the change in the load applied to the drive component ( 22 ), based on a difference in rotational speed between a time before and after injection of the learning injection amount of the fuel by the fuel injector ( 24 ). A fuel injection control apparatus according to claim 1, wherein the variation of the load applied to the drive member (10) 22 ), either a positive change of the load, which is oriented to the speed of the internal combustion engine ( 20 ), or is a negative change in the load, which is oriented to the speed of the internal combustion engine ( 20 ), and wherein the control device ( 50 ) determines at least the positive change of the load. A fuel injection control apparatus according to claim 1, wherein said control means ( 50 ) determines whether the drive component ( 22 ) and the driven component slip or not during rotation, and wherein, when it is determined that the drive component ( 22 ) and the driven component slip during a rotation, the control device ( 50 ) starts the injection quantity learning mode. Fuel injection control device for an internal combustion engine ( 20 ) with: a speed sensor ( 60 ), the speed of an internal combustion engine ( 20 ) measures; and a control device ( 50 ), which works to get a from a fuel injector ( 24 ) in the internal combustion engine ( 20 ) to control the amount of fuel to be injected, wherein, if necessary, an on to begin injection mode, the controller ( 50 ) the fuel injector ( 24 ) to inject a learning injection amount of the fuel that is an amount of fuel to the engine ( 20 ) fuel to be injected for learning a fuel injection characteristic of the fuel injector ( 24 ), the control device ( 50 ) determines a change in a load that is due to a drive component ( 22 ) of a torque transmission mechanism, by which an output torque of the internal combustion engine ( 20 ) of the drive component ( 22 ) is transmitted to a driven component, the control device ( 50 ) also an increase in the speed of the internal combustion engine ( 20 ) by the speed sensor ( 60 ) that has occurred due to the injection of the learning injection amount of the fuel, based on the number of revolutions of the engine ( 20 ) by the speed sensor ( 60 ) and the change in load applied to the drive component ( 22 ), the control device ( 50 ) also an actual injection quantity of the fuel, which is an amount of the fuel that is supposed to actually be discharged from the fuel injector ( 24 ) was injected on the basis of the increase in the number of revolutions of the internal combustion engine ( 20 ), the control device ( 50 ) calculates a correction factor based on a difference between the learning injection amount and the actual injection amount to determine the difference for instructing the fuel injector (FIG. 24 ) to inject a target amount of the fuel. A fuel injection control apparatus according to claim 10, wherein said control means ( 50 ) the change in the load on the drive component ( 22 ) acts on the basis of a change in the rotational speed of the internal combustion engine ( 20 ) between a time before and after injecting the learning injection amount of the fuel. A fuel injection control apparatus according to claim 10, wherein, when a load generating object is directly connected to the drive member (10). 22 ) is actuated, the control device ( 50 ) determines that the change in the load on the drive component ( 22 ), and also determines whether or not the absolute value of the variation of the load is greater than the predetermined value. A fuel injection control apparatus according to claim 10, wherein when an output signal from a brake sensor ( 70 ) an actuation of a brake pedal for the internal combustion engine ( 20 ), the control device ( 50 ) determines that the change in the load on the drive component ( 22 ), and also determines whether or not the absolute value of the variation of the load is greater than the predetermined value. A fuel injection control apparatus according to claim 10, wherein when a gear of a transmission ( 40 ), which is installed in the torque-transmitting mechanism is changed, the control device ( 50 ) determines that the change in the load on the drive component ( 22 ), and also determines whether or not the absolute value of the variation of the load is greater than the predetermined value. A fuel injection control apparatus according to claim 10, wherein said control means ( 50 ) the absolute value of the change in the load applied to the drive component ( 22 ), based on a difference in rotational speed between a time before and after injection of the learning injection amount of the fuel by the fuel injector ( 24 ). A fuel injection control apparatus according to claim 10, wherein the variation of the load applied to the drive member (10) 22 ), either a positive change of the load, which is oriented to the speed of the internal combustion engine ( 20 ), or is a negative change in the load, which is oriented to the speed of the internal combustion engine ( 20 ), and wherein the control device ( 50 ) determines at least the positive change of the load. A fuel injection control apparatus according to claim 10, wherein said control means ( 50 ) determines whether the drive component ( 22 ) and the driven component slip or not during rotation, and wherein, when it is determined that the drive component ( 22 ) and the driven component slip during a rotation, the control device ( 50 ) starts the injection quantity learning mode.